Swingarm stub axle thread size

[GSXR814]

Can anybody confirm what size thread is on the short stub axles that thread into the 'porkchops' and then into the swingarm bearings? 

My current thinking is M20 x 1.0 fine

[Lucky Phil]

37 minutes ago, GSXR814 said:

Can anybody confirm what size thread is on the short stub axles that thread into the 'porkchops' and then into the swingarm bearings? 

My current thinking is M20 x 1.0 fine

Depends on what year. There are 2 different sizes. The earlier red frame bikes had the fine thread in from memory 18mm and the later M20.

Phil 

[GSXR814]

44 minutes ago, Lucky Phil said:

Depends on what year. There are 2 different sizes. The earlier red frame bikes had the fine thread in from memory 18mm and the later M20.

Phil 

Mine is a later one so hopefully M20 fine👍

[GSXR814]

Next question.... 

I think I'm right in saying M20 x 2 is standard thread. 

So is fine M20 x 1.5 or M20 x 1.0?

Id like to get titanium ones so I don't really want to make an incorrect order! 

[GuzziMoto]

I think M20x2.5 is considered coarse thread, and M20x2.0 is considered fine thread. M20x1.5 is considered extra fine thread. I don't know if there is a M20x1.0 thread.

[GuzziMoto]

Also figure I would add that in metric bolts the thread value is the distance between each thread. So, the larger the bolt the higher the value all else being equal. And the smaller the bolt the lower the value. A larger diameter bolt will have a larger gap between threads when the thread is at the same pitch / angle.

[GSXR814]

4 hours ago, GuzziMoto said:

Also figure I would add that in metric bolts the thread value is the distance between each thread. So, the larger the bolt the higher the value all else being equal. And the smaller the bolt the lower the value. A larger diameter bolt will have a larger gap between threads when the thread is at the same pitch / angle.

OK. Thankyou. 

Any idea what size the threads are on the axle stubs? 

[Steve S]

Id like to get titanium ones so I don't really want to make an incorrect order!
 

okay I’ll ask the question….why?

[Lucky Phil]

Why Titanium? because the std ones are really quite heavy. Ti ones are on my list of things to machine up for my bike but I'd need to use a different method for holding them instead of an allan socket as i don't have a broaching tool. The thread will be MXX by 1.0mm I'm almost certain. I have a pair of large ones as spares that I can check later today. Important if you want to buy a replacement pork chop.

 

Phil 

[FreyZI]

10 hours ago, Lucky Phil said:

Depends on what year. There are 2 different sizes. The earlier red frame bikes had the fine thread in from memory 18mm and the later M20.

Here's a link to the discussion on the two different sizes:

And here's a pick of my spare M22 pivots up against the size/thread checker.  It's a very fine thread.

[gstallons]

Go to a tool store or auto parts store and purchase a metric thread gauge . Measure your pivot and you will have it. You can remove the jam nut so you can get access to the threads. 

[gstallons]

These pivots  in the red frame are smaller than the black frame pivots . 20mm x 1.0mm thread pitch  I have a pivot for the red frame in stock and that is what I measured . 1.0mm thread pitch . 

[gstallons]

I got these #s with an old vernier caliper and a metric thread file . I hope I am good at this conversion stuff

[Lucky Phil]

Corrections. Old size looks like M22 X 1.0 without pulling the locknut off. Later bikes definitely M24 X 1.0.

 

Phil

[FreyZI]

4 minutes ago, Lucky Phil said:

Corrections. Old size M20 X 1.0 Later bikes M24 X 1.0.

I dealt with the two different sizes when I swapped the side plates/pork chops/stilettos a couple years ago.  I measured both swing arm pivots with a digital caliper at 19.9 mm and 21.8 mm.  These numbers relate to the outside diameter of the threads.  I would call them M20 and M22, respectively.